Can anyone point me to a simple circuit that can be used to wire a MIC to a speaker so that the speaker can output the inputs to MIC. Also then I can connect the output from mic to micro controller to see the maximum and minimum voltage output of the MIC.

Can anyone point me to a simple circuit that can be used to wire a MIC to a speaker so that the speaker can output the inputs to MIC. Also then I can connect the output from mic to micro controller to see the maximum and minimum voltage output of the MIC.

Im a newbie, so please help me out. Thanks.

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What you need is an amplifier, but it is possible for something usually not wanted to happen if a microphone feeds a speaker so that the speaker can return the input to the microphone.

Have you heard what happens when a microphone is placed near the loudspeaker that it is feeding?

The non-inverting configuration has a conveniently high input impedance. Edit: As Bill Marsden points out, an inverting configuration would be possible, but this setup for a single-supply amplifier is quite commonly used. Perhaps trying to work out an inverting configuration would be a useful exercise, when you are ready for it.

Without a feedback loop the gain of an op-amp would have a very large but not closely specified value. The bandwidth would be low, and the linearity may be poor. The DC condition will be unstable, the output possibly limiting at one or other extreme value.

Perhaps such descriptions may not help much unless some underlying facts are also understood. Working "backwards" from a circuit may be confusing unless basic ideas such as bias, AC coupling, decoupling , feedback etc. are mastered first.

The circuit is a poor choice:
1) The LM358 has too much hiss and crossover distortion to be a mic preamp, use a low noise opamp like a TL071 instead (its minimum supply is 7V). The LM358 has two opamps but the TL071 is a single opamp (a TL072 is a dual and a TL074 is a quad).
2) Resistors R3 and R4 have values of only 4.7k which is much too low and they short most of the level from the mic. Use 47k for each of them instead.
3) The gain of the circuit is only 11 so you must scream loudly into the mic. Change R1 to 100k or 200k for a gain of 101 or 201.